Refrigerant flow distribution means



Nov. 12, 1963 K. M. GERTEIS REFRIGERANT FLOW DISTRIBUTION MEANS FiledFeb. 12, 1962 INVENTOR.

KARL M. GERTEIS ATTORNEY.

United States Patent 3,110,162 REFRIGERANI FLGW DISTRBUTION MEANS KarlM. Gerteis, dyracuse, N .Y., assignor to Carrier Corporation, Syracuse,N.Y., a corporation of Delaware Filed Feb. 12, 1962, Ser. No. 172,440 6Claims. (Cl. 62-196) This invention relates to air conditioningapparatus including a refrigeration system which can be operated underthe reverse cycle principle to provide either heating or cooling, moreparticularly to a refrigerant distributor having special utility in suchreverse cycle refrigeration systems for implementing the flow ofrefrigerant to the heat exchanger coils of the apparatus when therefrigerant flows to the coil, and facilitating bypass of the expansionmeans of the refrigeration system when the refrigerant flows from thecoil.

In that class of air conditioning apparatus employing a refrigerationsystem capable of operating on the reverse cycle principle to produceeither cooling or heating as desired, it is necessary to provide meanspermitting a bypass of the expansion valving normally arranged adjacentthe heat exchange coils. As is apparent to those skilled in the art,since the heat exchange coils of the reverse cycle refrigeration systemare alternatively employed for either heating or cooling, and since theexpansion valving necessary for the evaporation portion of therefrigerant cycle should be in close proximity to the coils functioningas an evaporator, separate expansion valving is provided adjacent eachgroup of heat exchanger coils. In order to permit any given coil of thereverse cycle refrigeration system to function alternatively as anevaporator or condenser, it is necessary to bypass the expansion valvingassociated with the coil, when the coil functions as a condenser.

Additionally, in relatively large installations a plurality of rows oftubes of substantial length are employed to form the heat exchangecoils. It is desirable to insure a uniformity of refrigerantdistribution to all of the tubes in the coil without excessive pressuredrop and to this end the refrigeration system is provided with adistributor feeding refrigerant from the line of the system to a numberof parallel circuit tubes.

It is accordingly a primary object of this invention to provide animproved refrigerant distributor valve serving the twofold purpose offeeding refrigerant simultaneously to a number of circuits in a heatexchanger coil when refrigerant is fed to the coil, and acting to permitbypassing of the expansion valving associated with the coil when therefrigerant cycle is reversed and the coil functions as a condenser.

A further object of the invention is to provide a combined expansionvalve member bypass and refrigerant distributor for a reverse cyclerefrigeration system.

Another object of the invention is to provide means permitting theelimination of the conventionally employed external check valve of aconventional heat pump.

The present invention relates to air conditioning apparatus of the typeincluding a refrigeration system which is selectively operable to coolor heat air. The refrigeration system includes a compressor, a firstheat exchange coil, and a first expansion member associated with saidcoil and a second heat exchange coil, and a second expansion member,said elements being connected in a closed "ice fluid circuit throughwhich refrigerant may flow. The first coil acts as an evaporator whenthe system is used for cooling. Also incorporated into the refrigerationcircuit is a reversing valve permitting the refrigerant to beselectively directed from the compressor either to said first coil or tosaid second coil, so that the first coil which functions as anevaporator during the cooling cycle acts as a condenser coil during theheating cycle. The aforesaid coils are of a mul'ti-tube, multi-circuittype, so that a refrigerant distributor is provided to feed uniformquantities of refrigerant to each circuit of the coil. Since the coilsare usually remotely located with respect to each other, separateexpansion members have been provided for each coil. As will beunderstood by those skilled in the art, only one of the expansionmembers will be active during each cycle of operation of therefrigeration system. Thus when the first coil is employed as anevaporator .the first expansion member is active, with the secondexpansion member being bypassed. To the organization described there isadded a novel refrigerant distributor for feeding refrigerant to thetubes of the coil, said distributor having means integral therewith forbypassing the inactive expansion member when refrigerant flows from thecoil.

An important feature of the invention resides in the provision of asingle valved member manipulatable as a unit in assembly of therefrigeration system which serves the twofold function of aiding inrefrigerant distribution when refrigerant flow therethrough is in onedirection, and aiding expansion member bypass when flow of therefrigerant is in an opposite direction.

The present invention will be more fully understood when the followingspecification is read in conjunction with the acompanying drawings,wherein:

FIGURE 1 is a schematic diagram of the air conditioning apparatus whichincludes a reverse cycle refrigeration system embodying the instantinvention; and

FIGURE 2 is an enlarged cross-sectional view through the novelrefrigerant distributor employed in the air conditioning apparatus ofFIGURE 1.

Referring now more particularly to the drawings like numerals will beemployed to designate like parts in the different figures.

As best seen in FIGURE 1, a refrigerant compressor 10 is coupled vialine 11 to four way valve 12 which permits flow of refrigerant from line11 through valve conduit 13 to line 14 which leads to first heatexchange coil 15-. Heat exchange coil is of a multi-tube type here shownas having two circuits 15a and 1517, but obviously subject to formationwith a greater number of tubes or circuits if desired, or as a singlecircuit coil.

Header distributor 16 of conventional type couples the tubes of the coilbetween line 14 and coil 15.

In the described orientation of four Way valve 12, as apparent to thoseskilled in the art, first coil 15 is coupled so that the coil functionsas a condenser in the illustrated refrigeration system.

Condensed refrigerant line 17 leads via intermediate line 19 and secondcoil line 2! to second heat exchange coil 22 which is of a multi-tubetype similar to first coil 15, and comprises coil circuits 22a and 22b.A second coil header 23 couples second coil 22 via line 24 to reversingfour way valve 12. Refrigerant flowing through line 24, in theillustrated orientation of valve 12, passes through valve conduit tocompressor suction line as.

A first fan 39 is arranged to direct air flow through first coil 15, anda second fan 31 is arranged to direct air through second coil 22, inconventional fashion.

Associated with first coil 15 is a first expansion member 35, andassociated with second coil 22 is a second expansion member 36illustrated in parallel flow relation with lines 17 and 29,respectively.

A first refrigerant distributor 4t; is arranged between first coil 15,expansion member 35 and refrigerant line 17. A second refrigerantdistributor 43a is arranged between second coil 22, second expansionmember 36 and refrigerant line 20. Refrigerant distributor 49 issubstantially identical to refrigerant distributor ida, except for apossible design variation in shape and capacity depending on thecapacity and construction of second heat exchanger 22. Refrigerantdistributor 46 will be described in specific detail, it being understoodthat this description is applicable to refrigerant distributor 40a.

As best seen in FIGURE 2, refrigerant distributor 40 comprises a housing41 having coil tube connections 42. and 43. Two coil tube connections 42and 43 are here shown to permit coupling to coil tube circuits 15a and151). It will, however, be understood by those skilled in the art thatthe number of coil tube circuit connections provided in the valvehousing are determined by the number of circuits comprising the coil towhich the housing is connected. A valve seat 44 is formed in the valvehousing 4-1 at an end of housing bore 45 closest to tube connections 42and 43. At the other end of housing bore 45 a valve stop 46 is formed. Asliding valve member 47 having circumferentially spaced longitudinalgrooves 470 and a metering orifice 48 is slid-ably positioned on aslideway in housing bore 45 so as to permit movement of the valve member47 between valve seat 44 and stop 46. The end of valve housing 41 remotefrom coil tube connections 42 and 4-3 is provided with a refrigerantline connection 5t), and a bypass connection 51 is formed in the valvebody to extend from bypass port 52 over which the valve member 47slides.

In use, the 'aforedescribed air conditioning system including arefrigeration system which can be operated under the reverse cycleprinciple is provided with the novel refrigerant distributor 4%? so asto eliminate the need for the conventionally employed external checkvalve.

The operation of the air conditioning system is initiated by energizingfans 30 and 31 along with compressor 18. With four Way valve 12 set inthe position illustrated in FIGURE 1, first coil 15 functions to provideheating of the air passing into heat exchange relationship with the coilsince coil 15 acts'as a heat dissipating refrigerant condenser in theillustrated refrigeration system. Refrigerant from compressor -10 flowsthrough conduit 13 of valve 12 to coil 15. From coil 15 the condensedrefrigerant flows into refrigerant distributor so. As viewed in FIGURE2, it will be noted that the flow of high pressure condensed refrigerantinto valve housing 41 causes valve member 47 to move toward valve seat45 opening bypass port 52 so that the condensed refrigerant will flowthrough line 17, bypassing expansion valve 35. Since the cross-sectionalarea of bypass port 52 is materially larger than that of meteringorifice 48, only a tiny portion of the condensed refrigerant will flowthrough the metering orifice 48 which is immaterial in terms ofrefrigerant system functioning since it occurs at the high pressure sideof the expansion member 35.

The condensed refrigerant flowing through line 17 fiows through line 19'to a second expansion member 36, second refrigerant distributor 40a andsecond heat exchange coil 22 which now functions as a heat absorbingrefrigerant evaporator.

When refrigerant from the expansion member 35 en ters refrigerantdistributor 49a as will be apparent from a consideration of thestructural detail shown in FIG- URE 2, valve body 47 is moved to theposition illustrated in the drawing closing off the port 52 associatedwith distributor 49a. Thus, the refrigerant from the expansion member 36is metered through metering orifice 48 in distributor 49a and fedthrough coil tube connections to evaporator coil 22 whence it isreturned to the suction side of compressor It).

A reversal of four way valve 12 orients conduit 13 to connect lines 11and 24 and valve conduit 25 to connect lines 14 and 26. With thisorientation of the valve '12, coil 22 functions as the condenser coil,and coil 15 functions as an evaporator coil. The above described mode ofoperation is accordingly reversed as will be apparent to those skilledin the art.

it is thus seen that a single device has been provided for incorporationinto a reverse cycle refrigeration system, with said device functioningto provide desired refrigerant distribution to a coil functioning as anevaporator, and implementing expansion member bypass when the said coilfunctions as a condenser.

The above disclosure has been given by way of illustration andelucidation, and not by way of limitation, and it is desired to protectall embodiments of the herein disclosed inventive concept within thescope of the appended claims.

I claim:

1. In air conditioning apparatus of the type including a refrigerationsystem operable on the reverse cycle to selectively heat or cool air,the combination of a refrigerant compressor having an inlet and anoutlet, first and second heat exchange coils coupled to said compressor,expansion means between said coils, valve means between said compressorand said coils permitting he selective coupling of either of said coilsto the inlet or outlet of said compressor, a refrigerant distributorbetween said expansion means and said coils, bypass means in saiddistributor, and valve means in said distributor V activating ordeactivating said bypass means in response to the direction ofrefrigerant flow through said distributor means.

2. In air conditioning apparatus as in claim 1, said valve means in saiddistributor comprising: a metering valve member slida ble over a bypassport.

3. In air conditioning apparatus as in claim 1 in which said valve meansin said distributor is slidably mounted to move in response torefrigerant pressure in the re frigera-tion system.

4. in air conditioning apparatus of the type including a refrigerationsystem operable on the reverse cycle to selectively heat or cool air,the combination of: a refrigerant compressor having an inlet and anoutlet; first and second heat exchange coils coupled to said compressor;first and second expansion members associated with said first and secondcoils respectively; a reversing valve between said compressor and saidcoils permitting the selective coupling of either of said coils to theinlet or outlet of said compressor; a first and second refrigerantdistributor associated respectively with said first and second coils; abypass connection from each of said distributors permitting bypass ofsaid expansion member associated with each of said cons; and a valvemember movably positioned in said distributor to open said bypassconnection when refrigerant flows to the coil associated with saiddistributor and to open said bypass connection when refrigerant flowsfrom the coil associated with said distributor, whereby the expansionmember associated with said coil will be inactive when said coilfunctions as a condenser in the refrigeration system.

5. Refrigerant distributor means comprising: coil connecting means forcoupling said distributor means to a heat exchanger coil; refrigerationline connecting means on said distributor means remote from said coilconnecting means; bypass connecting means on said distributor meansetween said coil connecting means and said refrigcrant line connectingmeans; and valve means movabie between said coil connecting means andline connecting means to open or close said bypass connecting means inresponse to whether refrigerant is flowing to said coil connecting meansor from said coil connecting means, said valve means opening said bypassconnecting means when refrigerant flows from said coil connecting means,and closing said bypass connecting means when refrigerant flows to saidcoil connecting means.

6. In a refrigerant distributor as in claim 5, said valve ReferencesCited in the fiie of this patent UNITED STATES PATENTS Burke Apr. 26,1960 Ray July 11, 1961

1. IN AIR CONDITIONING APPARATUS OF THE TYPE INCLUDING A REFRIGERATIONSYSTEM OPERABLE ON THE REVERSE CYCLE TO SELECTIVELY HEAT OR COOL AIR,THE COMBINATION OF A REFRIGERANT COMPRESSOR HAVING AN INLET AND ANOUTLET, FIRST AND SECOND HEAT EXCHANGE COILS COUPLED TO SAID COMPRESSOR,EXPANSION MEANS BETWEEN SAID COILS, VALVE MEANS BETWEEN SAID COMPRESSORAND SAID COILS PERMITTING THE SELECTIVE COUPLING OF EITHER OF SAID COILSTO THE INLET OR OUTLET OF SAID COMPRESSOR, A REFRIGERANT DISTRIBUTORBETWEEN SAID EXPANSION MEANS AND SAID COILS, BYPASS MEANS IN SAIDDISTRIBUTOR, AND VALVE MEANS IN SAID DISTRIBUTOR ACTIVATING ORDEACTIVATING SAID BYPASS MEANS IN RESPONSE TO THE DIRECTION OFREFRIGERANT FLOW THROUGH SAID DISTRIBUTOR MEANS.